The BMW Association is collaboratively working to develop pH TMDLs for Barr Lake and Milton Reservoir. Read this page to learn more about what TMDLs are and how the BMW Association is developing them.
What is a TMDL anyway?
Under section 303(d) of the 1972 Clean Water Act, states, territories, and authorized tribes are required to develop lists of impaired waters that do not meet water quality standards. In Colorado, this list is called the 303(d) List. Law requires that states, territories, and tribes establish priority rankings for waters on the lists and develop total maximum daily loads (TMDLs) for these waters. Barr Lake and Milton Reservoir were included on Colorado’s 2004 303(d) List with medium priority for elevated pH.
As defined by the U.S. EPA, a TMDL is a calculation of the maximum amount of a pollutant that a waterbody can receive and still meet water quality standards, and an allocation of that amount to the pollutant’s sources. In mathematical terms:
TMDL = LA + WLA + MOS
where LA is the nonpoint source load allocation, WLA is the point source waste load allocation, and MOS is a margin of safety.
Download Reports and Presentations
- Summary Report for Permit Number CO-0048837
- 2011 Water Quality Summary Series 6 Nitrogen Steve Lundt, Metro
- 2011 Water Quality Summary Series – Phosphorus Steve Lundt, Metro
- Part I - 2011 Water Quality Summary – pH Steve Lundt, Metro
- Part II – 2011 Water Quality Summary – chl-a Steve Lundt, Metro
- Part III Water Quality Summary – Dissolved Oxygen Steve Lundt, Metro
- Part IV Water Quality Summary – Temperature Steve Lundt, Metro
- TMDL final report
- Final Submitted TMDL Documents
- Barr Milton Phased TMDL Overview Steve Lundt, Metro
- TMDL Implementation Into Point Source Discharge Permits Janet Keiler, WQCD

